2004 Endeavor, cylinder 3 mifire.

Coil good(swapped from cylinder 5/no change), injector good(swapped from cylinder 5/no change), Plugs replaced(gap not altered), no coolant leakage into cylinder, intake manifold gasket in good shape, valve cover gaskets replaced.

Vehicle misfire at cold start up and occasionally during driving. Mostly at cold startup.

Our next step is to check for a possible sticking valve. Cylinder leakage test tested good. Compression test good.

Car had an alarm/remote start installed on it, causing an ecm fuse to blow, resulting in a tow in.

Has anyone come across any problems with the Endeavor resulting in a misfire in a single cylinder due to ECM issues? Or experieneced a misfire of this caliber caused by mechanical? 125,000 miles on the odo.

Again the misfire occurs mainly at cold startup and ends abrubtly not long after the vehicle warms.

Let me know thanks!

 

Upon looking into the vehicle again we noticed the #3 coil was faulty(the brand-new Mitsubishi coil replaced recently). A bulletine stated that the coils case expand due to overheating caused by a faulty ground(ground 11). Noticed a capacitor sharing the ground. Most likely put there for interference for that bank. Cleaned ground. This ground controlled the signal side of the ignition to detect of a misfire is occuring. If this ground is loose/faulty/oxidized it could cause the coil(s) to overheat, resulting in a new misfire. Still looking for experience with this problem.

 

Having a code for cylinder 3 as well. I have replaced the plugs. Replacing the coil now. Having a hard time finding info on where ground 11 is. Can anyone help?